[clang] [llvm] Support z17 processor name and scheduler description (PR #135254)

[via cfe-commits]

llvmbot wrote:

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Failed to cherry-pick: 80267f81482486977b3bdecf3855fc6a3096f912

https://github.com/llvm/llvm-project/actions/runs/14391420327

Please manually backport the fix and push it to your github fork.  Once this is done, please create a [pull request](https://github.com/llvm/llvm-project/compare)

https://github.com/llvm/llvm-project/pull/135254